U.S. patent application number 16/102877 was filed with the patent office on 2019-02-28 for seat for vehicle and designing method of the same.
This patent application is currently assigned to MAZDA MOTOR CORPORATION. The applicant listed for this patent is MAZDA MOTOR CORPORATION. Invention is credited to Yoshito HIRATA, Hiroaki MATSUBARA, Tomonori OHTSUBO, Hiroki UEMURA.
Application Number | 20190061568 16/102877 |
Document ID | / |
Family ID | 65321602 |
Filed Date | 2019-02-28 |
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United States Patent
Application |
20190061568 |
Kind Code |
A1 |
HIRATA; Yoshito ; et
al. |
February 28, 2019 |
SEAT FOR VEHICLE AND DESIGNING METHOD OF THE SAME
Abstract
In a seat for a vehicle which comprises a seat body, a slide
mechanism, and a lift mechanism, the lift mechanism is configured
such that a hip point of a specified physique occupant seated on
the seat body draws a track which is approximated to a virtual
rotational track of the hip point around a heel point when viewed
from a vehicle side, whereby a change quantity of an ankle's angle
is restricted below a first threshold and a change quantity of a
knee's angle is restricted below a second threshold.
Inventors: |
HIRATA; Yoshito;
(Hiroshima-city, JP) ; UEMURA; Hiroki;
(Hiroshima-city, JP) ; MATSUBARA; Hiroaki;
(Hiroshima-city, JP) ; OHTSUBO; Tomonori;
(Hiroshima-city, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
MAZDA MOTOR CORPORATION |
Hiroshima |
|
JP |
|
|
Assignee: |
MAZDA MOTOR CORPORATION
Hiroshima
JP
|
Family ID: |
65321602 |
Appl. No.: |
16/102877 |
Filed: |
August 14, 2018 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B60N 2/1615 20130101;
B60N 2/045 20130101; B60N 2/165 20130101; B60N 2/06 20130101 |
International
Class: |
B60N 2/16 20060101
B60N002/16; B60N 2/04 20060101 B60N002/04 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 23, 2017 |
JP |
2017-159954 |
Claims
1. A seat for a vehicle, comprising: a seat body arranged on a
vehicle floor and including a seat cushion; a slide mechanism
provided between the vehicle floor and the seat cushion and capable
of sliding the seat body within a specified range, in a
longitudinal direction, of the vehicle; and a lift mechanism
provided between the slide mechanism and the seat cushion and
capable of elevating/lowering the seat body within a specified
range, in a vertical direction, of the vehicle, wherein said lift
mechanism is configured such that a hip point of a specified
physique occupant seated on said seat body which changes according
to elevating/lowering of the seat body by the lift mechanism draws
a track approximated to a virtual rotational track of the hip point
around a heel point of the occupant when viewed from a vehicle
side, whereby a change quantity of an angle of an ankle of the
occupant is restricted below a first threshold and a change
quantity of an angle of a knee of the occupant is restricted below
a second threshold.
2. The seat for the vehicle of claim 1, wherein when said seat body
positioned in a specified region, in the longitudinal direction, of
the vehicle is elevated/lowered from one end to the other end of
said specified range, in the vertical direction, of the vehicle by
said lift mechanism, the track which the hip point of said occupant
draws is arranged such that the angle of the ankle of the occupant
falls in a first range and the angle of the knee of the occupant is
falls in a second range when viewed from the vehicle side.
3. The seat for the vehicle of claim 1, wherein said slide
mechanism comprises a rail which is attached to the vehicle floor
and a slider which is interposed between the rail and said lift
mechanism so as to slide along the rail, said seat cushion
comprises a frame member which is provided to extend in the
longitudinal direction along the slider, said lift mechanism
comprises a link member which is rotatably connected to the slider
at a front end portion thereof and rotatably connected to said
frame member at a rear end portion thereof, said rail and said
slider are provided to slant relative to a vehicle horizontal plane
such that front sides thereof are located at a higher level than
rear sides thereof, and said frame member is connected to said
slider such that the frame member slants with a front side thereof
being located at a higher level than a rear side thereof when the
seat body is positioned at a lower end of said specified range, in
the vertical direction, of the vehicle.
4. The seat for the vehicle of claim 2, wherein said slide
mechanism comprises a rail which is attached to the vehicle floor
and a slider which is interposed between the rail and said lift
mechanism so as to slide along the rail, said seat cushion
comprises a frame member which is provided to extend in the
longitudinal direction along the slider, said lift mechanism
comprises a link member which is rotatably connected to the slider
at a front end portion thereof and rotatably connected to said
frame member at a rear end portion thereof, said rail and said
slider are provided to slant relative to a vehicle horizontal plane
such that front sides thereof are located at a higher level than
rear sides thereof, and said frame member is connected to said
slider such that the frame member slants with a front side thereof
being located at a higher level than a rear side thereof when the
seat body is positioned at a lower end of said specified range, in
the vertical direction, of the vehicle.
5. The seat for the vehicle of claim 3, wherein the front end
portion of said link member is connected to said slider via a first
axial member extending in a vehicle width direction, the rear end
portion of said link member is connected to said frame member via a
second axial member extending in the vehicle width direction, and
said first axial member and said second axial member are provided
to overlap each other in the vertical direction when the seat body
is positioned at the lower end of the specified range, in the
vertical direction, of the vehicle.
6. A seat for a vehicle, comprising: a seat body arranged on a
vehicle floor and including a seat cushion; a slide mechanism
provided between the vehicle floor and the seat cushion and capable
of sliding the seat body within a specified range, in a
longitudinal direction, of the vehicle; and a lift mechanism
provided between the slide mechanism and the seat cushion and
capable of elevating/lowering the seat body within a specified
range, in a vertical direction, of the vehicle, wherein said slide
mechanism comprises a rail which is attached to the vehicle floor
and a slider which is interposed between the rail and said lift
mechanism so as to slide along the rail, said seat cushion
comprises a frame member which is provided to extend in the
longitudinal direction along the slider, said lift mechanism
comprises a front-side link member and a rear-side link member
which are provided to be spaced apart from each other in the
longitudinal direction and rotatably connected to the slider at
respective front end portions thereof and rotatably connected to
said frame member at respective rear end portions thereof, the
front-side link member being shorter than the rear-side link
member, said rail and said slider are provided to slant relative to
a vehicle horizontal plane such that front sides thereof are
located at a higher level than rear sides thereof, said frame
member is connected to said slider such that the frame member
slants with a front side thereof being located at a higher level
than a rear side thereof when the seat body is positioned at a
lower end of said specified range, in the vertical direction, of
the vehicle, the respective front end portions of said front-side
and rear-side link members are connected to said slider via
respective first axial members extending in a vehicle width
direction, the respective rear end portions of said front-side and
rear-side link members are connected to said frame member via
respective second axial members extending in the vehicle width
direction, and said respective first axial members and said
respective second axial members are provided to overlap each other
in the vertical direction when the seat body is positioned at the
lower end of the specified range, in the vertical direction, of the
vehicle.
7. A designing method of a seat for a vehicle comprising a seat
body, a slide mechanism capable of sliding the seat body within a
specified range, in a longitudinal direction, of the vehicle, and a
lift mechanism capable of elevating/lowering the seat body within a
specified range, in a vertical direction, of the vehicle, wherein
the seat for the vehicle is designed such that when said seat body
is elevated/lowered by said lift mechanism, a change quantity of an
angle of an ankle of a specified physique occupant seated on said
seat body is restricted below a first threshold and a change
quantity of an angle of a knee of the occupant is restricted below
a second threshold when viewed from a vehicle side.
8. The designing method of the seat for the vehicle of claim 7,
wherein an ideal region of a hip point of said occupant when viewed
from the vehicle side is set such that the angle of the ankle of
the occupant falls in a first range and the angle of the knee of
the occupant falls in a second range, and a structure of the seat
for the vehicle is designed such that a track which said hip point
of the occupant draws when said seat body positioned in a specified
region, in the longitudinal direction, of the vehicle is
elevated/lowered from one end to the other end of said specified
range, in the vertical direction, of the vehicle by said lift
mechanism is positioned in said ideal region when viewed from the
vehicle side.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a seat for a vehicle
provided with a lift mechanism and a designing method of the
same.
[0002] In general, there are provided a reclining mechanism to
adjust inclination of a seat back of a seat body, a slide mechanism
to adjust a position, in a longitudinal direction, of the seat
body, and a lift mechanism to adjust a position, in a vertical
direction, of the seat body at a driver's seat of an automotive
vehicle. A driver can drive the vehicle in an appropriate driving
position by adjusting the position of the seat body by means of the
above-described mechanisms according to a driver's physique (body
size).
[0003] As disclosed in Japanese Patent Laid-Open Publication No.
2008-24014, the lift mechanism of the seat for the vehicle
generally comprises a link mechanism which interconnects the slide
mechanism placed on a vehicle floor and the seat cushion of the
seat body. A link member which constitutes the link mechanism is
driven so as to rotate around an axis extending in a vehicle width
direction according to operation by an occupant, whereby the seat
body can be elevated or lowered.
[0004] Since elevating/lowering of the seat body by means of the
lift mechanism is achieved by a rotational move of the link member
as described above, the seat body is moved not only in the vertical
direction but in the longitudinal direction during its
elevating/lowering. In general, the seat body is moved obliquely
forward and upward when being elevated by the lift mechanism. In
this case, a hip point of the driver is suppressed from moving away
from a pedal, such as an accelerator pedal or a brake pedal, more
properly compared with a case where the seat body is moved straight
up.
[0005] Herein, the applicant of the present patent application has
been researched an ideal driving position from various perspectives
in order to develop the automotive vehicle which enables the driver
to drive the vehicle at will.
[0006] For example, it is desired for the driver to drive the
vehicle in a relaxed position from perspectives of securing the
operability of the pedal operated by the driver and reducing
fatigue of driver's legs. In order to attain the relaxed driving
position, it is requested that angles of respective joints of a
lower half body of the driver shown in FIG. 8 (an ankle's angle A,
a knee's angle B, and hip's angle C) fall in respective appropriate
ranges. Further, it is preferable that the position of driver's
eyes be set in an appropriate eye-line zone Z1 (see FIG. 1) from
perspectives of obtaining proper senses of speed and distance, a
sense of safety during high-speed driving, or the like.
[0007] In general, the ankle's angle A, the knee's angle B, and the
hip's angle C (see FIG. 3) are adjusted by the reclining mechanism
and the slide mechanism, and the eye's position (height) of the
driver is adjusted by the lift mechanism.
[0008] However, if the height adjustment by the lift mechanism is
conducted after the above-described joint angles A, B, C have been
adjusted by the slide mechanism and the like, there is a case where
the ankle's angle A and the knee's angle B so change according to
moving of a hip point HI that these angles A, B deviate from the
respective appropriate ranges. In this case, readjustment by the
slide mechanism and the like may be required for securing the
appropriate driving position.
SUMMARY OF THE INVENTION
[0009] Accordingly, an object of the present invention is to
provide a seat for a vehicle and a designing method of the same
which can simplify the adjustment of the driving position based on
a novel concept that a move track of the seat body operated by the
lift mechanism is optimized.
[0010] The present invention is a seat for a vehicle which
comprises a seat body arranged on a vehicle floor and including a
seat cushion, a slide mechanism provided between the vehicle floor
and the seat cushion and capable of sliding the seat body within a
specified range, in a longitudinal direction, of the vehicle, and a
lift mechanism provided between the slide mechanism and the seat
cushion and capable of elevating/lowering the seat body within a
specified range, in a vertical direction, of the vehicle, wherein
the lift mechanism is configured such that a hip point of a
specified physique occupant seated on the seat body which changes
according to elevating/lowering of the seat body by the lift
mechanism draws a track approximated to a virtual rotational track
of the hip point around a heel point of the occupant when viewed
from a vehicle side, whereby a change quantity of an angle of an
ankle of the occupant is restricted below a first threshold and a
change quantity of an angle of a knee of the occupant is restricted
below a second threshold.
[0011] Herein, an entire length of the "range, in the vertical
direction, of the vehicle" within which the seat body can be
elevated/lowered by the lift mechanism is constant regardless of
the position, in the longitudinal direction, of the seat body.
However, in a case where the position, in the vertical direction,
of the seat body changes according to moving, in the longitudinal
direction, of the seat body by means of the slide mechanism, the
height position of the "range, in the vertical direction, of the
vehicle" by the lift mechanism changes accordingly.
[0012] In the present description, the "hip point" is determined at
a single point according to the physique of the occupant and the
position of the seat body, and the "heel point" is determined at a
single point according to the physique of the occupant and the
position of an accelerator pedal. Therefore, if the position of the
accelerator pedal provided in the vehicle is constant, the heel
point is determined at a single point according to the occupant's
physique.
[0013] According to the above-described present invention, when the
seat body on which the specified physique occupant is seated is
elevated/lowered by the lift mechanism, the hip point of the
occupant moves so as to draw the track approximated to the virtual
rotational track of the hip point around the heel point of the
occupant when viewed from the vehicle side. Thereby, changing
(increase/decrease) of the distance between the heel point and the
hip point of the occupant is suppressed, so that the change
quantity of the ankle's angle of the occupant is restricted below
the first threshold and the change quantity of the knee's angle of
the occupant is restricted below the second threshold.
[0014] Thus, according to the present invention, as long as the
driving position has been previously adjusted by the slide
mechanism and the like so that the ankle's angle and the knee's
angle of the occupant fall in the appropriate range, even if the
height adjustment is conducted by the lift mechanism later, the
ankle's angle and the knee's angle can be properly maintained
within the appropriate range. Therefore, readjusting by means of
the slide mechanism and the like can be omitted after the height
adjustment by means of the lift mechanism, so that the adjustment
of the driving position can be simplified.
[0015] In an embodiment of the above-described invention, when the
seat body positioned in a specified region, in the longitudinal
direction, of the vehicle is elevated/lowered from one end to the
other end of the specified range, in the vertical direction, of the
vehicle by the lift mechanism, the track which the hip point of the
occupant draws is arranged such that the angle of the ankle of the
occupant falls in a first range and the angle of the knee of the
occupant is falls in a second range when viewed from the vehicle
side.
[0016] According to this embodiment, as long as the seat body has
been previously adjusted by the slide mechanism so as to be
positioned in the specified region in the longitudinal direction,
even if the seat body is elevated/lowered by the lift mechanism
later, the ankle's angle of the specified physique occupant and the
knee's angle of the specified physique occupant can be maintained
at respective appropriate angles in the first and second ranges.
Therefore, the readjusting by means of the slide mechanism and the
like can be omitted after the height adjustment by the lift
mechanism.
[0017] In another embodiment of the present invention, the slide
mechanism comprises a rail which is attached to the vehicle floor
and a slider which is interposed between the rail and the lift
mechanism so as to slide along the rail, the seat cushion comprises
a frame member which is provided to extend in the longitudinal
direction along the slider, the lift mechanism comprises a link
member which is rotatably connected to the slider at a front end
portion thereof and rotatably connected to the frame member at rear
end portion thereof, the rail and the slider are provided to slant
relative to a vehicle horizontal plane such that front sides
thereof are located at a higher level than rear sides thereof, and
the frame member is connected to the slider such that the frame
member slants with a front side thereof being located at a higher
level than region side thereof when the seat body is positioned at
a lower end of the specified range, in the vertical direction, of
the vehicle.
[0018] Herein, the "vehicle horizontal plane" described in the
present description means a plane which is perpendicular to the
vehicle vertical direction.
[0019] According to this embodiment, the rail and the slider of the
slide mechanism and the frame member of the seat cushion are both
configured to slant forward and upward relative to the vehicle
horizontal plane in a state where the seat body is positioned at
the lower end of the specified range, in the vertical direction, of
the vehicle. Thereby, the link member of the lift mechanism is
configured such that its front end portion connected to the slider
is positioned at a high level and its rear end portion connected to
the frame member is positioned at a lower level than the front end
portion. Accordingly, when the link member is rotated around its
connection portion to the slider by the operation of the link
mechanism, the connection portions to the link member and the frame
member draw a track which includes an arc part having its
tangential direction extending in the vehicle vertical direction in
an region which is configured to be narrow in the longitudinal
direction. Herein, the hip point which moves together with the
frame member draws a similar track in the region configured to be
narrow in the longitudinal direction.
[0020] Meanwhile, since a positional relationship between the heel
point and the hip point of the occupant is configured such that a
longitudinal distance between the heel point and the hip point is
sufficiently large, compared with a vertical distance between the
both, the virtual rotational track of the hip point around the heel
point includes an arc part having its tangential direction
extending in the vehicle vertical direction as well.
[0021] Accordingly, the track of the hip point which is actually
drawn during the elevating/lowering by the lift mechanism can be
arranged closely to the virtual rotational track of the hip point
around the heel point of the occupant in the region configured to
be narrow in the longitudinal direction (i.e., the
longitudinally-narrow region). Thereby, the changing
(increase/decrease) of the distance between the heel point and the
hip point of the occupant and the changing of the ankle's angle and
the knee's angle during the elevating/lowering by the lift
mechanism can be suppressed properly, so that the adjustment of the
driving position can be simplified effectively.
[0022] In another embodiment of the present invention, the front
end portion of the link member is connected to the slider via a
first axial member extending in a vehicle width direction, the rear
end portion of the link member is connected to the frame member via
a second axial member extending in the vehicle width direction, and
the first axial member and the second axial member are provided to
overlap each other in the vertical direction when the seat body is
positioned at the lower end of the specified range, in the vertical
direction, of the vehicle.
[0023] According to this embodiment, since the link member is
positioned such that the first axial member connecting the front
end portion of the link member to the slider of the slide mechanism
and the second axial member connecting the rear end portion of the
link member to the frame member of the seat cushion overlap each
other in the vertical direction when the seat body is positioned at
the lower end of the specified range, in the vertical direction, of
the vehicle, the adjustment of the driving position can be
simplified more effectively.
[0024] In another embodiment of the present invention, the link
member comprises a front-side link member and rear-side link member
which are provided to be spaced apart from each other in the
longitudinal direction, and the front-side link member is shorter
than the rear-side link member.
[0025] According to this embodiment, since the front-side link
member provided between the slide mechanism and the seat cushion is
shorter than the rear-side link member provided between the slide
mechanism and the seat cushion, there occurs a difference in the
radius between respective rotational tracks of the both link
members. Accordingly, the inclination of a seat face of the seat
cushion changes such that a relative height of a front end of the
seat cushion to a rear end of the seat cushion decreases when the
seat body is elevated by the lift mechanism. Thereby, the knee's
angle of the occupant is suppressed from becoming smaller than the
appropriate range, so that the ideal driving position can be
maintained properly.
[0026] Another aspect of the present invention is a designing
method of a seat for a vehicle comprising a seat body, a slide
mechanism capable of sliding the seat body within a specified
range, in a longitudinal direction, of the vehicle, and a lift
mechanism capable of elevating/lowering the seat body within a
specified range, in a vertical direction, of the vehicle, wherein
the seat for the vehicle is designed such that when the seat body
is elevated/lowered by the lift mechanism, a change quantity of an
angle of an ankle of a specified physique occupant seated on the
seat body is restricted below a first threshold and a change
quantity of an angle of a knee of the occupant is restricted below
a second threshold when viewed from a vehicle side.
[0027] According to the seat for the vehicle designed by the method
of the present invention, the change quantity of the ankle's angle
of the occupant is restricted below the first threshold and the
change quantity of the knee's angle of the occupant is restricted
below the second threshold when the seat body on which the
specified physique occupant is seated is elevated/lowered by the
lift mechanism. Therefore, according to the present invention, as
long as the driving position has been previously adjusted by the
slide mechanism and the like so that the ankle's angle and the
knee's angle of the occupant fall in the appropriate range, even if
the height adjustment is conducted by the lift mechanism later, the
ankle's angle and the knee's angle can be maintained within the
respective appropriate ranges properly. Accordingly, readjusting by
means of the slide mechanism and the like can be omitted after the
height adjustment by the lift mechanism, so that the adjustment of
the driving position can be simplified.
[0028] In an embodiment of the above-described method of the
present invention, an ideal region of a hip point of the occupant
when viewed from the vehicle side is set such that the angle of the
ankle of the occupant falls in a first range and the angle of the
knee of the occupant falls in a second range, and a structure of
the seat for the vehicle is designed such that a track which the
hip point of the occupant draws when the seat body positioned in a
specified region, in the longitudinal direction, of the vehicle is
elevated/lowered from one end to the other end of the specified
range, in the vertical direction, of the vehicle by the lift
mechanism is positioned in the ideal region when viewed from the
vehicle side.
[0029] According to the seat for the vehicle designed by the method
of this embodiment, as long as the seat body has been previously
adjusted by the slide mechanism so as to be positioned in the
specified region, in the longitudinal direction, of the vehicle
even if the seat body is elevated/lowered by the lift mechanism
later, the ankle's angle of the specified physique occupant and the
knee's angle of the specified physique occupant can be maintained
at the respective appropriate angles in the first and second
ranges. Therefore, the readjusting of the driving position by means
of the slide mechanism and the like can be omitted after the height
adjustment by means of the lift mechanism.
[0030] Other features, aspects, and advantages of the present
invention will become apparent from the following description which
refers to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a side view showing a seat for a vehicle according
to an embodiment of the present invention.
[0032] FIG. 2 is a side view showing a slide mechanism and a lift
mechanism of a seat shown in FIG. 1.
[0033] FIG. 3 is a side view showing a state where the seat is
moved forward by the slide mechanism, which is similar to FIG.
2.
[0034] FIG. 4 is a side view showing a state where the seat is
moved upward by the lift mechanism, which is similar to FIG. 2.
[0035] FIG. 5 is a diagram showing an ideal region of a hip point,
when viewed from a vehicle side.
[0036] FIG. 6 is a diagram showing a move track of the hip point,
when viewed from the vehicle side.
[0037] FIG. 7 is a diagram explaining a setting method of an
elevating/lowering track of the hip point.
[0038] FIG. 8 is a side view showing respective joint's angles
relating to a driving position of an occupant.
DETAILED DESCRIPTION OF THE INVENTION
[0039] Hereafter, an embodiment of the present invention will be
described referring to the drawings. Herein, unless there is any
particular description, the terms showing directions, such as
"forward," "rearward," "rightward," "leftward," "upward," and
"downward," mean respective directions relative to a vehicle in a
case where an traveling direction of the vehicle advancing forward
is the "forward" direction.
[0040] [Seat Structure]
[0041] As shown in FIG. 1, a seat 10 for a vehicle (hereafter,
referred to as "seat" simply) according to the present embodiment
is a driver's seat which is provided at a vehicle 1. In the present
embodiment, the vehicle 1 is a right-handle vehicle in which the
driver's seat 10 is arranged on the right side of the vehicle, but
the present invention is applicable to a left-handle vehicle in
which the driver's seat is arranged on the left side of the
vehicle.
[0042] In FIG. 1, reference character 2 denotes a floor panel,
reference character 3 denotes a bonnet (engine hood), reference
character 4 denotes a windshield, reference character 6 denotes an
accelerator pedal, reference character 8 denotes a steering wheel,
and reference character 100 denotes an occupant (driver) seated on
the seat 10.
[0043] The seat 10 comprises a seat body 13 which is arranged on
the floor panel 2. The seat body 13 comprises a seat cushion 14, a
seatback 18, and a headrest 19. The seat body 13 is supported at
the floor panel 2 via support members 11, 12 attached onto an upper
face of the floor panel 2, and a slide mechanism 20 and a lift
mechanism 30 (see FIG. 2) which are described later.
[0044] At a seat face of the seat cushion 14 are provided a hip
support portion 14a which supports the buttocks of the occupant 100
and a thigh support portion 14b which supports the femurs of the
occupant 100 at a position located in front of the hip support
portion 14a. The thigh support portion 14b is provided to slant
forward and upward.
[0045] Herein, the seat 10 may be provided with a seat-face tilt
mechanism (not illustrated) which adjusts an inclination angle of
the thigh support portion 14b. In this case, since the inclination
angle of the thigh support portion 14b is adjusted at an
appropriate angle by the seat-face tilt mechanism, it can be
suppressed that a back side of the femurs is pressed or a gap
occurs between the seat face and the femurs.
[0046] As shown in FIG. 2, the seat 10 is provided with a slide
mechanism 20 which is capable of sliding the seat body 13 within a
specified range, in a longitudinal direction, of the vehicle
(hereafter, referred to as a "slide range") and a lift mechanism 30
which is capable of elevating/lowering the seat body 13 within a
specified range, in a vertical direction, of the vehicle
(hereafter, referred to as an "elevating/lowering range").
[0047] Herein, the seat 10 is further provided with a reclining
mechanism (not illustrated) which is known for adjusting an
inclination angle of the seatback 18, specific description of which
is omitted here.
[0048] The slide mechanism 20 comprises a pair of right-and-left
rails 21 and a pair of right-and-left sliders 22. While the
right-side rail 21 and the right-side slider 22, when viewed from
an inward side, in the vehicle width direction, of the vehicle are
illustrated only in FIG. 2, the left-side rail and slider are
configured similarly to these right-side ones 21, 22.
[0049] The right-and-left rails 21 are arranged in parallel to each
other such that these extend in the longitudinal direction. The
rail 21 is a rail groove opened upward, for example. The rail 21 is
fixed to the floor panel 2 via the above-described support members
11, 12 (see FIG. 1). The rail 21 is provided to slant forward and
upward. An inclination angle of the rail 21 relative to a vehicle
horizontal plane is set at 6 degrees, for example.
[0050] The slider 22 is engaged with the corresponding rail 21 so
as to slide along this rail 21. The slider 22 is a long member
extending in the longitudinal direction. The slider 22 is provided
to slant forward and upward so as to correspond to the rail 21. A
pair of front-and-rear brackets 23, 24 which are connected to the
seat cushion 14 via the lift mechanism 30 are provided at the
slider 22.
[0051] The slider 22 can be locked at the rail 21 by a known lock
mechanism (not illustrated). Locking of the slider 22 by means of
the lock mechanism can be released through an operation of an
unlock lever by the occupant 100. In a state where the locking of
the slider 22 is released, the slider 22 can slide on the rail 21,
so that the seat body 13 can slide forward or rearward (see FIG.
3).
[0052] Referring to FIGS. 2 and 4, the structure of the lift
mechanism 30 will be described. FIG. 2 shows the lift mechanism 30
when the seat body 13 is positioned at a lower end of an
elevating/lowering range of the seat body 13, and FIG. 4 shows the
lift mechanism 30 when the seat body 13 is positioned at an upper
end of the elevating/lowering range of the seat body 13.
[0053] The lift mechanism 30 connects the slider 22 of the slide
mechanism 20 to the seat cushion 14. The lift mechanism 30 is
connected to the seat cushion 14 at a pair of right-and-left side
frames 15 which make a framework of the seat cushion 14.
[0054] Herein, while only the right-side side frame 15 is
illustrated in FIGS. 2 and 4, the left-side side frame is formed
similarly.
[0055] The side frame 15 is provided to extend in the vehicle
longitudinal direction at a side portion of the seat cushion 14.
The side frame 15 is arranged along the slider 22 at a position
located above and closely to the slider 22.
[0056] The right-and-left side frames 15 are interconnected via a
pair of connecting shafts 16, 17 extending in the vehicle width
direction, for example. The pair of connecting shafts 16, 17 are
spaced apart from each other in the longitudinal direction. The
front-side connecting shaft 16 is provided at a position, in the
longitudinal direction, between a front end portion and a central
portion of the side frame 15. The rear-side connecting shaft 17 is
positioned near at a rear end of the side frame 15.
[0057] The lift mechanism 30 is provided with a link mechanism 31
which connects the slider 22 and the side frame 15. The link
mechanism 31 comprises a front-side link member 33 and a rear-side
link member 34. The link mechanism 31 is provided at each of the
right and left sides of the seat.
[0058] Herein, while only the right-side link mechanism 31 (the
right-side front-side link member 33 and the right-side rear-side
link member 34) is illustrated in FIGS. 2 and 4, the left-side link
mechanism is formed basically similarly.
[0059] The front-side link member 33 is a plate-shaped member
extending linearly. A direction P1 where the front-side link member
33 extends (inclination angles Q1, Q11 of the front-side link
member 33 relative to a vehicle horizontal plane SO) changes
according to the position, in the vertical direction, of the seat
body 13, but one end portion of the front-side link member 33 is
always arranged in front of the other end portion of the front-side
link member 33.
[0060] A front end portion of the front-side link member 33 is
rotatably connected to the front-side bracket 23 of the slide
mechanism 20 via a connecting pin 35 having an axial center
extending in the vehicle width direction. A rear end portion of the
front-side link member 33 is rotatably connected to the side frame
15 of the seat cushion 14 via the above-described front-side
connecting shaft 16.
[0061] The rear-side link member 34 is a plate-shaped member
extending linearly. The rear-side link member 34 is longer than the
front-side link member 33. A direction P2 where the rear-side link
member 34 extends (inclination angles Q2, Q12 of the rear-side link
member 34 relative to the vehicle horizontal plane SO) changes
according to the position, in the vertical direction, of the seat
body 13, but one end portion of the rear-side link member 34 is
always arranged in front of the other end portion of the rear-side
link member 33.
[0062] A front end portion of the rear-side link member 34 is
rotatably connected to the rear-side bracket 24 of the slide
mechanism 20 via a connecting pin 36 having an axial center
extending in the vehicle width direction. A rear end portion of the
rear-side link member 34 is rotatably connected to the side frame
15 of the seat cushion 14 via the above-described rear-side
connecting shaft 17.
[0063] As described above, the front-side link member 33 and the
rear-side link member 34 are rotatably connected to the slide 22
via the brackets 23, 24 at their front end portions and rotatably
connected to the side frame 15 at their rear end portions.
[0064] As shown in FIG. 2, the rear-side link member 34 which is
one of the right-and-left rear-side link members 34 (the right-side
link member 34 in the present embodiment) is configured to be
rotatably driven by a drive mechanism 40. The drive mechanism 40
comprises an operational lever 41, a rotation control device 42, a
drive shaft 43, a pinion gear 44, and a sector gear 45.
[0065] The operational lever 41 is arranged beside the seat cushion
14 (on the right side in the present embodiment). The operational
lever 41 is provided to extend in the longitudinal direction such
that its tip end portion is positioned forward and its base end
portion is positioned rearward. The operational lever 41 is
configured such that it is pulled up when the seat body 13 is
elevated and it is pushed down when the seat body 13 is lowered.
Further, the operational lever 41 is configured such that a biasing
force generated by a biasing means (not illustrated) is applied
thereto when operations for its pulling up or its pushing down are
conducted by the occupant 100 and it is returned to its initial
position by the above-described biasing force when applying an
operational force thereto by the occupant 100 is released.
[0066] The drive shaft 43 is provided to extend in the vehicle
width direction, and connected to the base end portion of the
operational lever 41 via the rotation control device 42. When the
operational lever 41 is pulled up, the drive shaft 43 is rotated
clockwise in FIG. 2, and when the operational lever 41 is pushed
down, the drive shaft 43 is rotated counterclockwise in FIG. 2.
When the drive shaft 43 is rotationally driven, the link mechanism
31 is operated as described later, so that the seat body 13 is
elevated or lowered.
[0067] When the operational lever 41 is not operated, the rotation
of the drive shaft 43 is restricted by the operation control device
42, so that it is suppressed that the seat body 13 is elevated or
lowered by an intentional input of a vertical load or the like.
Herein, since any known structure is possibly adopted as the
rotation control device 42, describing its specific structure is
omitted here.
[0068] The pinion gear 44 is provided on the drive shaft 43 so as
to be rotated together with the drive shaft 43. The sector gear 45
is provided in back of and adjacently to the pinion gear 44 and
engages with the pinion gear 44. The sector gear 45 is integrally
provided with the rear-side link member 34, for example. However,
the sector gear 45 may be fixed to the rear-side link member 34.
Teeth of the sector gear 45 are arranged in a circumferential
direction around a shaft center of the rear-side connecting shaft
17 at a front portion of the rear-side connecting shaft 17.
[0069] When the pinion gear 44 is rotated, together with the drive
shaft 43, according to the operation of the operational lever 41,
the sector gear 45 and the rear-side link member 34 are integrally
rotated around the connecting shaft 17 in an opposite direction to
the rotational direction of the pinion gear 44.
[0070] More specifically, when the pinion gear 44 is rotated
clockwise in FIG. 2 according to the pulling-up operation of the
operational lever 41, the sector gear 45 and the rear-side link
member 34 are rotated counterclockwise around the connecting shaft
17 in FIG. 2. Herein, since moving of the front end portion of the
rear-side link member 34 is restricted by the connecting pin 36,
the rear-side link member 34 is rotated around the connecting shaft
17 and also rotated counterclockwise around the connecting pin 36
in FIG. 2.
[0071] Thereby, the rear-side link member 34 is rotationally driven
such that the relative height of its rear end to its front end
increases. Herein, the front-side link member 33 is also rotated in
response to the rotation of the rear-side link member 34 such that
the relative height of its rear end to its front end increases.
Thus, the position of the front-and-rear link members 33, 34
changes from a lying position shown in FIG. 2, for example, to a
rising position shown in FIG. 4, for example, so that the seat body
13 is elevated.
[0072] To the contrary, when the operational lever 41 is pushed
down, the pinion gear 44 and the sector gear 45 are rotated in the
opposite direction to the above-described direction, so that the
front-and-rear link members 33, 34 are rotated in the opposite
direction to the above-described direction. Thus, the position of
the front-and-rear link members 33, 34 changes from the rising
position shown in FIG. 4, for example, to the lying position shown
in FIG. 2, for example, so that the seat body 13 is lowered.
[0073] Herein, another drive mechanism may be provided in place of
the above-described drive mechanism 40. In this case, the drive
mechanism may be electrical, not limited to being manual.
[0074] As shown in FIG. 2, when the seat body 13 is positioned at
the lower end of the elevating/lowering range of the seat body 13,
the side frame 15 of the seat cushion 14 is provided to slant
forward and upward relative to the vehicle horizontal plane,
corresponding to the rail 21 and the slider 22 of the slide
mechanism 20.
[0075] Further, in the state shown in FIG. 2, the rear-side link
member 34 is provided to slant rearward and slightly upward
relative to the vehicle horizontal plane SO, so that it takes a
lying position along the vehicle horizontal plane SO. Herein, it is
preferable that the inclination angle Q2 of the longitudinal
direction P2 of the rear-side link member 34 (an extensional
direction of a straight line which connects an axial center of the
connecting pin 36 and an axial center of the connecting shaft 17)
be set at an angle within 0 to 10 degrees, and set at 5 degrees in
an example shown in FIG. 2. Herein, the connecting pin 36 and the
connecting shaft 17 are provided to overlap each other in the
vehicle vertical direction.
[0076] Herein, since the link mechanism 31 is configured such that
the front-side link member 33 is shorter than the rear-side link
member 34, the radius of the rotational track of the front-side
link member 33 is smaller than that of the rotational track of the
rear-side link member 34. Accordingly, inclination of the seat face
of the seat cushion 14 changes such that the relative height of its
front end to its rear end decreases when the seat body 13 is
elevated. Thereby, the knee's angle B of the occupant 100 is
suppressed from becoming smaller than the appropriate range.
[0077] As shown in FIG. 4, when the seat body 13 is positioned at
the lower end of the elevating/lowering range, the seat frame 15 of
the seat cushion 14 is arranged substantially along the vehicle
horizontal plane SO. At this time, the inclination angle Q12 of the
rear-side link member 34 becomes greater than the inclination angle
Q2 in the state shown in FIG. 2, within a range from 40 degrees to
50 degrees, for example. Further, at this time, the inclination
angle Q11 of the front-side link member 33 becomes greater than the
inclination angle Q1 in the state shown in FIG. 2, and also becomes
greater than the inclination angle Q12 of the rear-side link member
34.
[0078] [Driving Position]
[0079] The driving position of the occupant 100 seated on the seat
10 (see FIG. 1) will be described referring to FIG. 8.
[0080] Each of the ankle's angle A, the knee's angle B, and the
hip's angle C of the occupant 100, when viewed from the vehicle
side, has the appropriate range for achieving the ideal driving
position. The appropriate range of the ankle's angle A is generally
within a range from 90 degrees to 100 degrees in a state where the
occupant 100 just places a foot on the accelerator pedal 6 (see
FIG. 1), without pressing the accelerator pedal 6 (an accelerator
opening angle is zero), for example. The appropriate range of the
knee's angle B is generally within a range from 119 degrees to 132
degrees, for example. The appropriate range of the hip's angle C is
generally within a range from 90 degrees to 110 degrees, for
example.
[0081] The ankle's angle A and the knee's angle B of the occupant
100 are determined based on a heel point HE, a knee point KN, and a
hip point HI.
[0082] The heel point HE is determined at a single point according
to the physique (body size) of the occupant 100 and the position of
the accelerator pedal 6 (see FIG. 1). In the present embodiment,
since the accelerator pedal 6 is fixed at a specified position of
the vehicle 1, the heel point HE is determined at a single point
according to the physique (body size) of the occupant 100 only.
[0083] Meanwhile, the hip point HI is determined according to the
physique (body size) of the occupant 100 and the position of the
seat body 13, and the heel point KN is determined according to the
heel point HE and the hip point HI.
[0084] In the present descriptions, the heel point means a contact
point of the heel with the vehicle floor when the occupant is
seated in the seat, having a specified angle between a shoe sole
surface and the accelerator. The knee point means the position of a
knee joint of the occupant. The hip point means the position of a
joint of a thighbone. For example, these points correspond to the
followings in SAE mannequin defined in the standard by SAE (SAE
Standard).
[0085] Heel Point: HOS (Heel of Shoe)
[0086] Knee Point: Intersection point of Leg Line and Thigh
Line
[0087] Hip Point: H-Point
[0088] Accordingly, by positioning the seat body 13 by the slide
mechanism 20 and the lift mechanism 30, the heel point HE, the knee
point KN, and the hip point HI are all determined, so that the
ankle's angle A and the knee's angle B are determined.
[0089] Herein, since the hip's angle C changes according to the
inclination of the upper half body of the occupant 100, this angle
C is determined according to the inclination adjustment of the seat
back 18 (see FIG. 1) by the reclining mechanism (not illustrated),
in addition to the positioning of the seat body 13 by the slide
mechanism 20 and the lift mechanism 30.
[0090] [Ideal Region of Hip Point]
[0091] An ideal region R1 where the hip point HI is arranged for
achieving the ideal driving position is a region which can make the
ankle's angle A and the knee's angle B fall in the above-described
respective appropriate ranges.
[0092] FIG. 5 shows an example of the ideal region R1 of the hip
point HI, when viewed from the vehicle side. A setting method of
the ideal region R1 shown in FIG. 5 is as follows.
[0093] First, a lower limit of the appropriate range of the ankle's
angle A is set as a first ankle's angle A1, an upper limit of the
appropriate range of the ankle's angle A is set as a second ankle's
angle A2, a lower limit of the appropriate range of the knee's
angle B is set as a first knee's angle B1, and an upper limit of
the appropriate range of the knee's angle B is set as a second
knee's angle B2. Further, the hip point HI when the ankle's angle A
is the first ankle's angle A1 and the knee's angle B is the first
knee's angle B1 is set as a first point X1, the hip point HI when
the ankle's angle A is the first ankle's angle A1 and the knee's
angle B is the second knee's angle B2 is set as a second point X2,
the hip point HI when the ankle's angle A is the second ankle's
angle A2 and the knee's angle B is the first knee's angle B1 is set
as a third point X3, and the hip point HI when the ankle's angle A
is the second ankle's angle A2 and the knee's angle B is the second
knee's angle B2 is set as a fourth point X4.
[0094] In a case where the heel point HE is fixed at the single
point, when the ankle's angle A falls in the appropriate region
between the first ankle's angle A1 and the second ankle's angle A2
and also the knee's angle B falls in the appropriate region between
the first knee's angle B1 and the second knee's angle B2, the hip
point HI always falls in the region R1 enclosed by the first point
X1, the second point X2, the third point X3, and the fourth point
X4. Accordingly, this region R1 can be set as the ideal region of
the hip point HI for achieving the ideal driving position.
[0095] Strictly speaking, in an outline of the ideal region R1 of
the hip point HI, a line connecting the first point X1 and the
second point X2 and a line connecting the third point X3 and the
fourth point X4 are an arc having its center at the knee point KN,
and a line connecting the first point X1 and the third point X3 and
a line connecting the second point X2 and the fourth point X4 are
an arc having its center at a rotational axis of a lower side of a
lower part of a body (near the heel point HE).
[0096] Herein, a region enclosed by the line connecting the first
point X1 and the second point X2, the line connecting the second
point X2 and the fourth point X4, the line connecting the fourth
point X4 and the third point X3, and the line connecting the third
point X3 and the first point X1 may be set as the ideal region R1
of the hip point HI, for convenience.
[0097] [Track of Hip Point]
[0098] FIG. 6 is a side view showing a track TS of the hip point HI
of the occupant 100 when the seat body 13 is slid by the
above-described slide mechanism 20 and a track TL of the hip point
HI of the occupant 100 when the seat body 13 is elevated/lowered by
the above-described lift mechanism 30, when viewed from the vehicle
side.
[0099] More specifically, FIG. 6 shows a first slide track TS1
which the hip point HI draws when the seat body 13 positioned at
the lower end of the elevation/lowering range moves from a front
end H11 to a rear end H12 of the slide range and a second slide
track TS2 which the hip point HI draws when the seat body 13
positioned at the upper end of the elevation/lowering range moves
from a front end H21 to a rear end H22 of the slide range as the
track TS at the time of the slide move.
[0100] Further, FIG. 6 shows a first elevating/lowering track TL1
which the hip point HI draws when the seat body 13 positioned at
the front end of the slide range moves from the lower end H11 to
the upper end H21 of the elevating/lowering range and a second
elevating/lowering track TL2 which the hip point HI draws when the
seat body 13 positioned at the rear end of the slide range moves
from the lower end H12 to the upper end H22 of the
elevating/lowering range as the track TL at the time of the
elevating/lowering.
[0101] Since the seat body 13 is movable within the specified slide
range and the specified elevating/lowering range, the hip point HI
of the occupant 100 always exists in a movable region R2 which is
enclosed by the first slide track TS1, the second slide track TS2,
the first elevating/lowering track TL1, and the second
elevating/lowering track TL2.
[0102] In a case where the ideal region R1 of the hip point HI
determined above and the movable region R2 where the hip point HI
can be arranged overlap each other, the ideal driving position of
the occupant 100 where the ankle's angle A falls in the appropriate
range (the range from the first ankle's angle A1 to the second
ankle's angle A2) and the knee's angle B falls in the appropriate
range (the range from the first knee's angle B1 to the second
knee's angle B2) can be achieved by positioning the hip point HI in
this overlapping region R3.
[0103] [Designing of Seat]
[0104] Designing of the seat 10 will be conducted as follows for
simplifying the adjustment of the driving position to make the hip
point HI fall in the above-described overlapping region R3, for
example.
[0105] First, the lower limit A1 and the upper limit A2 of the
appropriate rage of the ankle's angle A and the lower limit B1 and
the upper limit B2 of the appropriate rage of the knee's angle B
are set, and the ideal region R1 (see FIG. 5) of the hip point HI
of the specified physique occupant 100 are set based on these
appropriate ranges by the above-described method.
[0106] The position of the above-described set ideal region R1 of
the hip point HI is a relative position to the heel point HE. As
shown in FIGS. 6 and 7, this set ideal region R1 is a rectangular
region enclosed by the four lines. The ideal region R1 is the
elongated region having a shorter longitudinal length than a
vertical length.
[0107] An average body size of an adult male may be adopted as the
specified physique occupant 100, for example. As an example of this
adopted body size, the physique of AM50 established by the United
States Standard (the average body size of the U.S. adult male) is
used.
[0108] Subsequently, the above-described overlapping region R3 is
set. The overlapping region R3 is determined by the ideal region R1
of the hip point HI and a positional relation between the first
slide track TS1 and the second slide track TS2. Accordingly, it is
required that specific arrangements of the ideal region R1, the
first slide track TS1, and the second slide track TS2 in the
vehicle 1 are determined in order to set the overlapping region
R3.
[0109] The arrangement of the ideal region R1 in the vehicle 1 is
determined according to the heel point HE, and the heel point HE is
determined based on the position of the accelerator pedal 6 (see
FIG. 1). The arrangements of the first slide track TS1 and the
second slide track TS2 in the vehicle 1 are determined according to
the arrangement and shape of the seat body 13, the structure of the
slide mechanism 20, the elevating/lowering range of the lift
mechanism 30 and others.
[0110] A specific example of the arrangements of the first slide
track TS1 and the second slide track TS2 in the setting of the
overlapping region R3 will be described referring to FIG. 7.
[0111] In the example shown in FIG. 7, the first slide track TS1 is
arranged such that it crosses the line connecting the first point
X1 and the third point X3 at the outline of the ideal region R1 and
also passes through the fourth point X4, and the second slide track
TS2 is arranged such that it crosses the line connecting the first
point X1 and the second point X2 and the line connecting the second
point X2 and the fourth point X4 at the outline of the ideal region
R1. In this case, a pentagonal region which is interposed between
the first slide track TS1 and the second slide track TS2 in the
ideal region R1 is set as the overlapping region R3.
[0112] Herein, the first slide track TS1 may be arranged such that
it passes through a position which is upward or downward offset
from the fourth point X4 of the ideal region R1. In a case where
the first slide track TS1 is arranged such that it passes through
the position which is downward offset from the fourth point X4, the
outline of the ideal region R1 is hexagonal.
[0113] Herein, it is preferable that the eye position of the
occupant 100 always fall in the appropriate eye-line zone Z1 (see
FIG. 1) when the hip point HI of the above-described specified
physique occupant 100 is positioned in the overlapping region R3.
Accordingly, it is preferable that this point of view be considered
in setting of the height of the first slide track TS1 and the
second slide track TS2 (in setting of the elevating/lowering
range).
[0114] Subsequently to the setting of the overlapping region R3,
the track TL which the hip point HI draws when the seat body 13 is
elevated/lowered by the lift mechanism 30 (hereafter, referred to
as an "elevating/lowering track TL of the hip point HI" or the
"elevating/lowering track TL") is set.
[0115] The elevating/lowering track TL of the hip point HI is
determined according to the structure of the lift mechanism 30,
such as the length and the inclination angle of the respective
links 33, 34 and the distance between the front and rear link
members 33, 34.
[0116] The elevating/lowering track TL of the hip point HI is set
so as to fall in the overlapping region R3. For example, when a
lower end H1 of the elevating/lowering track TL is arranged at a
rear end (the fourth point X4 in the example shown in FIG. 7) of a
portion of the first slide track TS1 which crosses the ideal region
R1, an upper end H2 of the elevating/lowering track TL is arranged
at a portion of the second slide track TS2 which crosses the ideal
region R1.
[0117] By setting the elevating/lowering track TL as described
above, the hip point HI of the specified physique occupant 100 can
be always made to fall in the ideal region R1 when the seat body 13
positioned in a specified region, in the longitudinal direction, of
the vehicle is elevated/lowered by the lift mechanism 30. In this
case, when the seat body 13 whose longitudinal position is properly
adjusted by the slide mechanism 20 is elevated or lowered by the
lift mechanism 30, the ankle's angle A and the knee's angle B of
the specified physique occupant 100 can be securely maintained in
the respective appropriate ranges.
[0118] Further, according to the above-described setting of the
elevating/lowering track TL, a change quantity of the ankle's angle
A of the specified physique occupant 100 is restricted below a
first threshold and a change quantity of the knee's angle B of the
specified physique occupant 100 is restricted below a second
threshold when the seat body 13 is elevated or lowered by the lift
mechanism 30.
[0119] Herein, the above-described first threshold is an angle
which corresponds to a difference between the upper limit A2 and
the lower limit A1 in the appropriate range of the ankle's angle A,
and the above-described second threshold is an angle which
corresponds to a difference between the upper limit B2 and the
lower limit B1 in the appropriate range of the knee's angle B.
[0120] Specifically, it is preferable that the first threshold be 5
degrees or greater and 15 degrees or smaller, which is set at 10
degrees, for example. It is preferable that the second threshold be
10 degrees or greater and 15 degrees or smaller, which is set at 13
degrees, for example. Herein, these thresholds are not to be
limited to particular angles, particularly.
[0121] The elevating/lowering track TL of the hip point HI is set
as described above, and then the respective specific structures of
the seat 10 including the lift mechanism 30 is designed such that
the seat body 13 is elevated or lowered so as to attain this set
elevating/lowering track TL.
[0122] Since the ideal region R1 is the elongated region having the
shorter longitudinal length (i.e., the longitudinally-narrow
region) as described above, the overlapping region R3 which is part
of the ideal region R1 has a shorter length in the longitudinal
direction (see FIG. 7). Accordingly, it is required to configure
the elevating/lowering track TL to be short in the longitudinal
direction in order to make the elevating/lowering track TL fall in
the overlapping region R3. The following can be considered as an
example of the seat 10 to meet the above-described requirement.
[0123] As shown in FIG. 2, each of the rail 21 and the slider 22 of
the slide mechanism 20 and the side frame 15 of the seat cushion 14
is configured to slant forward and upward relative to the vehicle
horizon plane SO in the state where the seat body 13 is positioned
at the lower end of the elevating/lowering range. Thereby, the
front-and-rear link members 33, 34 of the lift mechanism 30 are
arranged such that each of their front end portions connected to
the slider 22 is located at a higher level and each of their rear
end portions connected to the side frame 15 is located at a lower
level, so that these link members 33, 34 take the lying position
such that their rear end portions are located at the lower level
than their front end portions.
[0124] More specifically, the front-side link member 33 is provided
to take the lying position such that the connecting pin 35
supporting its front end portion and the connecting shaft 16
supporting its rear end portion overlap each other in the vertical
direction. The rear-side link member 34 is provided to take the
lying position such that the connecting pin 36 supporting its front
end portion and the connecting shaft 17 supporting its rear end
portion overlap each other in the vertical direction.
[0125] Accordingly, in order to elevate the seat body 13 from the
position shown in FIG. 2, the connecting shafts 16, 17 draw the
respective tracks including the arc portions having their
tangential directions extending along the vertical direction in the
longitudinally-narrow region when the front-and-rear link members
33, 34 and the connecting shafts 16, 17 are rotated around the
connecting pins 35, 36. Herein, since the hip point HI of the
occupant 100 is elevated together with the connecting shafts 16, 17
and the side frame 15, the hip point HI draws the
elevating/lowering track TL in the longitudinally-narrow region as
well (see FIG. 4).
[0126] Herein, as shown in FIG. 6, in a case where the hip point HI
moves along a virtual rotational track TO around the heel point HE,
a distance L1 between the heel point HE and the hip point HI is
maintained constant, so that the ankle's angle A and the knee's
angle B of the occupant 100 can be properly suppressed from
changing.
[0127] Meanwhile, the radius of the actual elevating/lowering track
TL of the hip point HI is determined according to the structures of
the link mechanism 31, such as the rotational radius of the link
members 33, 34. However, it is not realistic from a layout view
point to configure the link members 33, 34 such that their length
is substantially equal to the distance L1 between the heel point HE
and the hip point HI. Accordingly, the radius of the
elevating/lowering track TL of the hip point HI becomes
considerably smaller than the radius of the above-described virtual
rotational track TO.
[0128] Therefore, the conventional seat for a vehicle is configured
such that deviation between the actual elevating/lowering track TL
of the hip point HI and the virtual rotational track TO is large,
which causes a large change of the ankle's angle A or the knee's
angle B when the seat body 13 is elevated or lowered.
[0129] Meanwhile, according to the present embodiment, the
elevating/lowering track TL of the hip point HI is set to be fall
in the longitudinally-narrow overlapping region R3, the
elevating/lowering track TL can be provided to be approximated to
the above-described virtual rotational track TO as shown in FIG. 7.
Therefore, the change (increase/decrease) of the distance L1 (see
FIG. 6) between the heel point HE and the hip point HI of the
occupant 100 can be suppressed effectively in the
elevating/lowering of the seat body 13, so that the change of the
ankle's angle A and the knee's angle B of the occupant 100 can be
effectively suppressed.
[0130] Thus, according to the present embodiment, as long as the
driving position is previously adjusted by the slide mechanism 20
so that the ankle's angle A and the knee's angle B of the occupant
100 fall in the appropriate range, even if the height adjustment is
conducted by the lift mechanism 30 later, the ankle's angle A and
the knee's angle B can be maintained within the appropriate range
properly. Further, even if the ankle's angle A and the knee's angle
B deviate from the appropriate range, this deviation can be reduced
effectively. Therefore, readjusting by means of the slide mechanism
20 and the like can be omitted after the height adjustment by the
lift mechanism 30, so that the adjustment of the driving position
can be simplified.
[0131] While the present invention has been described referring to
the above-described embodiment, the present invention is not to be
limited to this embodiment.
[0132] For example, while the above-described embodiment shows the
example (see FIG. 7) in which the elevating/lowering track TL is
set so as to fall in the overlapping region R3 which is determined
by the previously-set ideal region R1, the first slide track TS1,
and the second slide track TS2 in the design of the seat 10, the
step of setting the track of the hip point HI is not limited to
this example. For example, the elevating/lowering track TL is set
to fall in the ideal region R1 may be set first, and subsequently
the first slide track TS1 and the second slide track TS2 may be set
so as to pass through the upper end and the lower end of the
elevating/lowering track TL.
[0133] Further, while the above-described embodiment shows the
example in which the single ideal region R1 which corresponds to
the single physique (body size) of the occupant is set and the seat
10 is configured such that the elevating/lowering track TL falls in
the ideal region R1, plural ideal regions which correspond to
plural physiques (body sizes) may be set and the seat 10 may be
configured such that the elevating/lowering tracks of the
respective hip points of the plural physiques (body sizes) falls in
the respective ideal regions.
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